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9 USING A LINEAR SERVO MOTOR
9.4 Basic function
Linear servo control error detection function
If the linear servo control becomes unstable for some reason, the linear servo motor may not operate properly. To detect this
state and to stop operation, the linear servo control error detection function is used as a protective function.
The linear servo control error detection function has three types of detection methods: the position deviation, speed deviation,
and thrust deviation. An error is detected when each method is enabled with [Pr. PL04.0 [AL. 042 Servo control error]
detection function selection]. The detection level can be changed with [Pr. PL05 Position deviation error detection level], [Pr.
PL06 Speed deviation - Error detection level], and [Pr. PL07 Torque deviation error detection level].
Precautions
• For the linear servo control error detection function, the position and speed deviation error detections are enabled before
shipping. ([Pr. PL04.0]: 3)
Linear servo control error detection selection function
Select the linear servo control error detection function.
• [Pr. PL04.0 [AL. 042 Servo control error] detection function selection]
Refer to the following table.
Initial value: 3
■
Position deviation error detection
Set [Pr. PL04.0 [AL. 042 Servo control error] detection function selection] to "1" to enable the position deviation error
detection.
When the difference between the model feedback position ( 1)) and the feedback position ( 2)) in the figure is equal to or more
than the value of [Pr. PL05 Position deviation error detection level] (1 mm to 1000 mm), [AL. 042.1 Servo control error by
position deviation] occurs and the linear servo motor stops. The initial value of this detection level is 50 mm. Change the
setting value as necessary.
Setting value
Position deviation error detection
Speed deviation error detection
Thrust deviation error detection
1
Enabled
Disable
Disable
2
Disable
Enabled
Disable
3
Enabled
Enabled
Disable
4
Disable
Disable
Enabled
5
Enabled
Disable
Enabled
6
Disable
Enabled
Enabled
7
Enabled
Enabled
Enabled
Servo parameter
Description
PL04.0
[AL. 042 Servo control error] detection function selection
1: Position deviation error detection enabled
Servo amplifier
Servo amplifier internal value
Linear servo motor
1) Model feedback position [mm]
3) Model feedback speed [mm/s]
5) Command thrust [%]
Linear encoder
Linear encoder
2) Feedback position [mm]
4) Feedback speed [mm/s]
6) Feedback thrust [%]
